Comminutor



June 1,1943. A. c. DURDIN, JR

COMMINUTOR Fi led March 10, 19:59

2 Sheets-Sheet l 1NVENTOR. ail/ 70:721.? 6. flardm J f (Q.

ATTORNEY.

June 1, 1943. c N, JR 2,320,514

COMMINUTOR Filed March 10, 1939 2 Sheets-Sheet 2 INVENTOR. Muguflfm 6. Dam/1'0, J/t

ATTORNEY.

Patented June 1, 1943 UNITED STATES PATENT OFFICE COMMINUTOR Augustus C. Durdin, Jr., Lincolnweod, Ill.

Application March 10, 1939, Serial No. 261,067

3 Claims.

This invention relates to comminutors and more particularly to that character of comminutor which operates to intercept solids and semisolids in a' flowing stream, and to reduce the same to pieces small enough to pass through the comminutor along with the flow of liquid. More specifically, the present comminutor relates to that type which permits the liquid and comminuted solids to pass transversely through a rotating slotted straining element, of which the slots are usually formed by spaced discs mounted on a motor driven shaft.

The principal object of this invention is to provide a comminutor of improved construction and operation and having a rotating transversely slotted straining element which intercepts the solids and semi-solids, and is provided on its circumference with a multiplicity of cutting teeth that cooperate with a slotted cutting bar to comminute the intercepted material.

Another object is to provide a rotating, comminuting and'straining element in which the slots are so designed as to permit solids and semi-solids that might become wedged in the slots to be released and washed out of the slots by the flowing liquid. Another object is to provide means for positively clearing the slots of any solid or semi-solid pieces that may become wedged therein. Another object is to provide a form of discs that enable material to gravitate through the i slots. Another object is to provide means to prevent sand, dirt and grit from entering the lower bearing of the rotating comminuting and straining element.

Other objects and advantages will appear in the course of this specification and, with said objects and advantages in view, this invention c0nsists in the several novel features hereinafter fully set forth and claimed.

,- The invention is clearly illustrated in the drawings accompanying this specification, in which:

Fig. 1 is a view partly in side elevation and .partly in cross-section of a comminutor emb0dying the preferred former the invention mounted in a channel.

Fig. 2 is a horizontal section taken on the line 2-2 of Fig. 1 showing fragments of the side walls .of the channel adjacent the comminutor.

Fig. 3 is a detail. vertical section illustrating a modified form of discs embodied in the comminiu tor.

Fig. 4 is a vertical cross-section illustrating a second modified form of discs.

Fig. 5 is a vertical cross-section illustrating a third modified form of discsand showing in connection therewith the fingers for clearing the slots between the discs.

Fig. 6 is a vertical cross-section illustrating a fourth modification of the invention.

Referring to said drawings, and first to Figs. 1 and 2 which illustrate the preferred form of the invention, the reference character it designates a channel, usually formed of concrete side walls H, 12 and a bottom I 3. A stream of sewage or other liquid containing solids and semi-solids flows through the channel from any source to a plant for further treatment. While the comminutor shown and described herein has been designed for straining liquids and comminuting intercepted solids and semi-solids contained in sewage, it is to be understood that its use is not limited thereto.

The comminutor is interposed in the channel, which as a preference, may be constructed in accordance with the specification and drawings of my co-pending application for patent on Channel construction for comminute-rs, Serial No. 261,006, filed March 10, 1939, now Patent No. 2,241,587, dated May 13, 1941, to which reference may be had for a more complete explanation of its construction and operation. As shown, the normal or transverse cutting axis of the comminutor is disposed at an angle of forty-five degrees to the longitudinal axis of the channel, but this may be varied as desired.

The comminuting and straining element of the comminutor comprises a' series of discs I 4 mounted on and keyed to a drive shaft I5 and spaced apart as by hubs 16 to provide slots or passageways that extend transversely of the shaft. The discs may be flat so as to provide straight slots between them for the passage of liquids and comminuted solids and semi-solids. A frame comprising a top plate I! and a base plate l8 connected by uprights 19 forms the support for the rotating comminuting and straining element and other associated parts. The shaft is journaled in bearings 20, 2|, carried by the top and base plates and is connected to the shaft of an electric motor 22 mounted on the top plate I! as by a motor base 24.

The lowermost disc of the series rests on an inverted cup shaped bearing member 25, and a collar 26 pinned to the shaft above the uppermost disc holds them tightly together. On the circumferences of the discs are rigidly fastened cutting teeth 27 which cooperate with a notched cutting bar 28 to comminute solids and semi-solids caught between the cutting bar and teeth. The teeth pass through the notches of the cutting bar and cut or shear oif small pieces of the material, reducing the same to a small enough size to be unobjectionable in the further treatment of the sewerage, or small enough to pass through the slots between the discs. The cutting bar is bolted or otherwise fastened to one of the upright frame members l9 and the inner face of the channel wall H, adjacent the cutting bar, is arranged to direct the flow of the liquids and solids in a direction parallel with and along the face of the cutting bar 28 toward its notched edge (see Fig. 2). Desirably, a bar 23 is fastened to the other upright I9 for the purpose of closing the gap between the upright and the rotating comminuting and straining element. The uprights 19 may be embedded in the concrete side walls of the channel whereby to anchor the frame solidly therein.

The annular flange 29 of the lower bearing member 25 rotates in an annular groove 32, which is formed in a stationary bearing member 3| cast integral with and projects down from the base plate 18. A bearing bushing 34 is placed between the shaft and the inner face of the bearing member 3|. ings 20 are housed in a housing 35 formed on the underside of the top plate I! and carry the weight of the rotating comminuting and straining member.

A flanged seal ring 36 fastened to the base plate and contacting with the edge of the lowermost disc prevents grit, sand, rags and other material from entering the space between the base plate and lowermost disc, and a flanged seal ring 31 secured to the base plate bears against the face of the cup shaped bearing member 25 and prevents any dirt, grit, sand, rags or other material that might possibly leak past the seal ring 36 from entering the lower bearing. An oil duct 31 leads down from the top plate H to the bottom member of the lower bearing member 3] and supplies lubricant to the lower bearing. Grease forced through the duct to the lower bearing resists the free entrance of grit or dirt to the bear- On the discharge side of the comminutor is an upright post 38 (see Fig. 2) supported by the top and base plates ll, l8, and projecting from said post are fingers or scrapers 39, preferably curved as shown, that enter the slots between the discs and serve to discharge any comminuted solids or semi-solids that may have become lodged in the slots. 7

In the operation of the comminutor illustrated in Figs. land 2, the motor rotates the rotating comminuting and straining element in the direction of the arrow thereon in Fig. 2. Solids and semi-solids that are carried thereto by the flowing stream, which are too large to pass through the slots along with the flow of liquid, are intercepted by the edges of the discs and are pressed against the same by the pressure of the flowing stream. The rotating comminuting and straining element carries this material to the notched cutting bar where the cutting teeth out, shear 01' tear up small pieces from the material, which small pieces pass with the flowing stream through the slots although some of them may pass along the edges of the discs without passing through the slots. As the rotating comminuting and straining elementrotates, some of the comminuted pieces may lodge between the discs adjacent the edges where they entered and may be carried around to the opposite side of the axis of rotation. The flowing stream then acts to wash Anti-friction thrust bearthem out through the slots at the edges where they entered the slots. Any pieces that may have become too firmly wedged between the discs encounter the fingers 39 and are positively removed from the slots.

In the modified form of a rotating comminuting and straining element illustrated in Fig. 3, the to and bottom faces of adjacent discs ll converge or taper slightly from the edges of the discs towards the center thereof, thus providing slots or passages whose faces converge from the edges of the discs towards the center. With this form of slots, any small pieces of material that enter the slots and become wedged between the discs are readily released and washed out of the slots by the flowing stream when the wedged pieces have been carried around to a place where the faces of the slots diverge from the center and outwardly as the discs are traveling along the discharge side of the comminutor.

In the modified form illustrated in Fig. 4, the discs M are dished upwardly so as to provide downwardly sloping faces on both sides of the discs. This form of disc facilitates the discharge of solids and semi-solids, such as sand or grit, because these particles may gravitate down the sloping faces of the discs along with the flow of the liquid through the slots.

In the form of the discs H illustrated in Fig. 5, the edges of the discs are thickened so as to form marginal ribs W which are spaced apart the required distance to control the size of the comminuted pieces that may pass through the slots. It will also be observed that in this case the slots inwardly of the ribs are considerably wider than the spaces between the ribs N If desired, the fingers or scrapers 39 described in connection with the preferred form of the invention may be used in connection with the type of discs illustrated in Fig. 5.

In the modified form of the invention illustrated in Fig. 6, the upwardly dished form of disc Hi is employed, and the edge portions of said discs are thickened on their lower sides to provide marginal ribs l4 that are spaced from the upper faces of the adjacent discs. This type of dished disc has the advantage that sand, grit and other material may gravitate down the sloping faces of the disc and may freely escape therefrom. The fingers or scrapers 39 are shown in connection with this form of disc and in this case they are bent upwardly to extend at the same angle as the slope of the discs.

In other respects, the modified forms of discs shown may be employed in a comminutor in which the supporting frame and notched cutting bar may be made substantially in accordance with the corresponding parts illustrated in Figs. 1 and 2.

I claim as new and desire to secure by Letters Patent:

l. A comminutor comprising a series of spaced d scs mounted on a driving shaft and providing slots between adjacent discs through which liquids and comminuted solids are directed by said discs to pass from an inlet side of the comminutor to the opposite side thereof, said slots being free and unobstructed on the entire inlet side of the comminutor, whereby a maximum amount of liquid may pass through the slots, the edges of said spaced discs on the inlet side of the comminutor providing means to intercept solids and semi-solids in a stream flowing to the comminutor, cutting teeth projecting from the edges of the discs, means to rotate said shaft, and a stationary notched cutting bar cooperating with said cutting teeth to reduce solids into small pieces, said cutting bar being mounted with its notched edge adjacent the series of disc edges, and the notches disposed in the paths of travel of the cutting teeth, In combination with side and bottom walls forming a channel through which flows a stream of liquids containing solids and semi-solids, the comminutor being interposed in the channel and substantially spanning the gap between the side walls thereof, and a portion of one side wall of the channel adjacent the comminutor being disposed approximately in the plane of the upstream side face of the cutting bar and arranged to direct the flow of liquids, solids and semi-solids along said face of the cutting bar toward its notched edge.

2. A comminutor comprising a slotted body composed of a series of spaced discs mounted on a driving shaft and providing slots between adjacent discs through which liquids and comminuted solids are directed by said discs to pass from an inlet side of the comminutor to the opposite side thereof, said slots being free and unobstructed on the entire inlet side of the comminutor, whereby a maximum amount of liquid may pass through the slots, the edges of said spaced discs on the inlet side of the comminutor providing means to intercept solids and semi-solids in a stream flowing to the comminutor, cutting teeth projecting u with its notched edge adjacent the series of disc edges, and the notches disposed in the paths of travel of the cutting teeth, in combination with side and bottom walls forming a channel through which flows astream of liquids containing solids and semi-solids, the comminutor being inter posed in the channel and substantially spanning the gap between the side walls thereof with the cutting bar disposed on the upstream side of the comminutor body and extending edgewise therefrom in a direction which is less than a right angle to the longitudinal aXis of the channel, and a portion of one side wall of the channel adjacent the comminutor being disposed approximately in the plane of the upstream side face of the cutting bar and arranged to direct the flow of liquids, solids and semi-solids along said face of the cutting bar towards its notched edge.

3. A comminuter comprising a cylindrical rotatina body having spaced slots extendin transversely through of, said slots being free and unobstructed at the inlet side of the comminutor, the cylindrical face of said body being adapted to intercept solids and semi-solids in a flowing stream and the slots permitting the flow of liquid and comminuted material thercthrough, from the inlet side of the comminutor to the opposite side thereof, a multiplicity of cutting teeth projecting from the cylindrical face of the body, means to rotate said body, and a coacting stationary notched cutting bar disposed adjacent the face of said body with the notches disposed in the paths of travel of the cutting teeth, the cutting teeth and the edges of the notches cooperating to out small pieces from solids and semi-solids lodged between the cutting bar and teeth, in combination with side and bottom walls forming a channel through which flows a stream of liquids containing solids and semisolids, the comminutor being interposed in the the body from side to side therechannel and substantially spanning the gapbetween the side Walls thereof and a portion of one sidewall of the channel adjacent the comminutor being disposed approximately in the plane of the upstream side face of the cutting bar and arranged to direct the flow of liquids, solids and semi-solids along said face of the cutting bar towards its notched edge.

4. A comminutor comprising a series of coaxial, spaced discs, means for securing the discs to provide a body of cylindrical form having slots therethrough spaced by the discs and through which liquids and comminuted solids may pass from an inlet side of the comminutor to the opposite side thereof, said slots being free and unobstructed on the entire inlet side of the comminutor, whereby a maximum amount of liquid may pass through the slots, the cylindrical face of the body being adapted to intercept solids and semi-solids in a flowing stream, a multiplicity of cutting teethprojecting from the edges of the discs, means to rotate said body, and a co-acting stationary notched cutting bar mounted adjacent the disc edges, with the notches disposed in the paths of travel of the cutting teeth, in combination with side and bottom walls forming a channel through which flows a stream of liquids containing solids and semi-solids, the comminutor being interposed in the channel and substantially spanning the gap between the side walls thereof, and a portion of one side wall of the channel adjacent the comminutor being disposed approximately in the plane of the upstream side face of the cutting bar and arranged to direct the flow of liquids, solids and semi-solids along said face of the cutting bar toward its notched edge.

5. A comminutor comprising a shaft, a series of spaced, upwardly dished discs mounted on the shaft with their peripheral edges disposed below their central portions, means to rotate the shaft cutting teeth on the edges of the discs, and a notched cutting bar mounted contiguous with the disc edges, with the notches disposed in the paths of travel of the cutting teeth, in combination with side and bottom walls forming a channel through which flows a stream of liquids containing sol ds and semi-solids, the comminutor being disposed in the channel and substantially spanning the gap between the side walls thereof, and a portion of one side wall of the channel adjacent the comminutor being disposed approximately in the plane of the cutting bar, and arranged to direct the flow of the liquids, solids and semi-solids along the face of the cutting bar towards its notched edge.

6. A commihutor comprising a shaft and a plurality of spaced discs mounted thereon, the edge portions of said discs being thickened to provide annular ribs, cutting teeth on the edges of the discs, means to rotate the shaft, and a notched cutting bar mounted contiguous with the d sc edges, with the notches disposed in the paths of travel of the cutting teeth, in combination with side and bottom walls forming a channel through which flows a stream of liquids containing solids and semi-solids, the comminutor being disposed in the channel and substantially spann'ng the gap between the side walls thereof, and a portion of one side wall of the channel adjacent the comminutor being disposed approximately in the plane of the cutting bar, and arranged to direct the flow of the liquids, solids and semi-solids along the face of the cutting bar towards its notched edge.

7. A comminutor comprising a shaft, a series of upwardly dished discs mounted thereon with their peripheral portions disposed below their central portions and formed with downwardly projecting annular ribs at their edges, cutting teeth on the edges of said discs, means to rotate the shaft, and a notched cutting bar mounted contiguous with the disc edges, with the notches disposed in the paths of travel of the cutting teeth, in combination with side and bottom walls forming a channel through which flows a. stream of liquids containing solids and semi-solids, the comminutor being disposed in the channel and substantially spanning the gap between the side walls thereof, and a portion of one side wall of the channel adjacent the comminutor being disposed approximately in the plane of the cutting bar, and arranged to direct the flow of the liquids, solids and semi-solids along the face of the cutting bar towards its notched edge.

8. A comminutor comprising ashaft, a series ,of spaced discs mounted thereon and provided with cutting teeth on their edges, means to rotate the shaft, a notched cutting bar mounted contiguous with the edges of the discs, with'the notches disposed in the paths of travel of the cutting teeth, and fingers mounted on a support and extending into the slots between the discs on the downstream side of the comminutor and adapted to scrape out solids caught in the spaces between the discs, in combination with side and bottom walls forming a channel through which flows a stream of liquids containing solids and semi-solids, the comminutor being interposed in the channel and substantially spanning the gap between the side walls thereof, and a portion of one side wall of the channel adjacent the comminutor being disposed approximately in the plane of the cutting bar, and arranged to direct the flow of the liquids, solids and semi-solids along tle face of thecutting bar towards its notched e ge.

AUGUSTUS C. DURDIN, JR. 

